A Method for Evaluation of Leakage Risk Area in the Process of CO2 Geological Storage

Abstract

A kind of CO 2 The evaluation method of the leakage risk area during the geological storage process uses the principle of sedimentary microfacies constraint, how to obtain the rock mechanical parameters of the caprock, and select a suitable fracture pressure prediction model to evaluate the mechanical sealing of the caprock, using fine geological models and numerical values. Model, applying reservoir numerical model theory, and in-depth study of CO through the established storage volume numerical model 2 Injection process until storage for 200 years to store pressure and CO in the body 2 Dynamic changes in saturation. Using the concepts of fluid potential and potential gradient in oil and gas migration theory combined with CO 2 Saturation dynamic distribution analysisCO 2 migration direction and accumulation area, and then according to the CO in the storage body 2 The migration direction and distribution characteristics of the storage body and sand body boundary are combined to conduct lateral CO 2 Leakage risk prediction; Based on the rupture pressure distribution characteristics of the caprock and the dynamic distribution characteristics of the pressure in the storage body, CO is quantitatively studied through the proposed identification formula of the caprock rupture risk area. 2 Possible leakage risk areas longitudinally along the migration path. This method is used in low permeability reservoir CO 2 It has important practical application value to achieve safe and efficient carbon sequestration during oil displacement.

Description

Technical field [0001] This invention belongs to CO 2 The field of safety assessment of geological storage, involving a kind of CO 2 CO during geological storage 2 Through the comprehensive evaluation and prediction method of the risk area of ​​the cover layer leakage. Background technique [0002] Climate change is a common challenge facing human society today, reducing CO in the atmosphere 2 It has become a global consensus to protect the human environment. In various emission reduction schemes, CO 2 CCS-Carbon Capture and Storage technology can significantly reduce the CO produced by fossil fuels in the atmosphere. 2 Emissions have great potential for emission reduction and are valued by countries all over the world. And in the existing CO 2 In geological storage technology, CO 2 Injecting into abandoned or mid- and late-stage oil and gas fields for flooding and storage is preferred by countries all over the world for its economic efficiency. CO stored in oil and gas reservoi...

AI Technical Summary

Problems solved by technology

This method focuses on solving the problem of obtaining cap rock mechanical parameters and selecting a fracture pressure prediction model when the core data of the reservoir and cap rock are insufficient and unmatched; CO 2 Dynamic change of pressure in the storage body and CO 2 The dynamic distribution of transport accumulation and CO 2 Prediction method of leakage risk area

Images